In order to move the tool from a working to a rest position thereof it has already been suggested to rotate the upright about its vertical axis thus causing an angular movement of the tool, or to incline the upright whereby partly rotating it about a horizontal axis, e.g. provided at base of the upright.
Accidents may occur when the upright is subjected to an angular movement, and thus a specific lateral protection is required about the upright which would unduly increase the production costs.
When the solution according to which the upright is inclined rearwards after having been partly rotated about a horizontal axis is adopted on an assembling-disassembling machine, a large area behind the machine is to be provided. In most cases such an area is not ready available without cost increase. Furthermore, according to such a solution in order to move the working tool between its working and rest positions a relatively large weight has to be displaced each time which might result in substantial unbalance in the machine. Moreover, with such a machine the times for tool “opening” are relatively long since the weight of the upright with its respective tool-carrying arm is heavy, and a slow opening is to be carried out in order to prevent the machine from being overturned.
Another drawback of such a tool system that provides for displacing the tool away from its working position is that the working area available for the operator (tyreman) to carry out other tyre disassembling from or mounting onto a wheel rim located on the self-centring group is limited even after upright has been (partly) overturned rearwards. Such a circumstance can be a penalizing factor for the operator's movements around and above the rotatable support group and accidents may occur owing to the presence of the tool hanging near the supporting group.